When molecular ions are accelerated to high velocities (0.03c) and passed through extremely thin (50 \AA) Formvar targets their valence electrons are stripped off, initiating molecular dissociation on a time scale much shorter $(10^{-17})$ than vibrational and rotational motion. The individual atoms from the explosion event are detected in coincidence via a novel $detector^{1}$ that measures their relative moments. This information can be uniquely related to the structure of the molecule. The ""Coulomb explosion"" technique has been used to determine the structure of several carbo-cations $e.g.,^{2}$ ($C_{2}H_{3}^{+3}$ and $CH_{4}^{+}$) and represents a powerful new technique for investigating the structure and vibrational motions of molecular ions. This work supported by the U. S. Department of Energy, Office of Basic Energy Sciences, under Contract W-31-109-ENG-38.